Archery bow spring-biased plunger



Dec. 9, 1969 N. L. PINT v ,4

ARCHERY BOW SPRING-BIASED PLUNGER Filed July 15. 196'? INVENTOR. NORMAN L. PINT ATTORNE United States Patent 3,482,563 ARCHERY BOW SPRING-BIASED PLUNGER Norman L. Pint, Blairs Ferry Road NE, Rte. 2, Marion, Iowa 52302 Filed July 13, 1967, Ser. No. 653,088 Int. Cl. F14b /00 U.S. Cl. 12424 3 Claims ABSTRACT OF THE DISCLOSURE A device which engages the side of an arrow shaft as it lies on the rest and which moves into the bow as the arrow passes to prevent the arrow from striking the bow. The side pressure is adjustable as is the total movement of the device.

This invention relates in general to bows and arrows and in particular to an attachment in or on a bow which engages the side of an arrow and which is easily retracted by the arrows action as it passes over the bow.

As archers become more and more experienced they become more accurate. In their quest for further improvement, equipment is sought to absorb irregularities in shooting form, thereby providing additional consistancy from shot to shot. A few irregularities minimized by the arrows, action as it passes over the bow. variations in release.

As an arrow is released by an archer, the bow tends to turn in his hand and the arrow shaft normally deflects around the bow window. An improper shot could cause the arrow to strike the guide post or bow producing an erratic arrow flight.

It is an object of this invention to provide a plunger (guide post) of adjustable length and tension which engages the side of the arrow shaft during sighting and which collapses into the bow as the shaft passes the bow.

Another object is to provide a spring loaded plunger mounted in a bow which provides greater accuracy.

A feature of this invention is found in the provision for a spring loaded plunger which engages the shaft of an arrow while it lies on the rest and retracts from the shaft during the flight past the bow and which may be adjusted transversely of the bow and in tension to improve the accuracy of the archer.

Further features, advantages and objects will become apparent from the following descriptions and claims when read in view of the drawings, in which;

FIGURE 1 is a partially cutaway view of the plunger assembly of this inventionmounted in a bow;

FIGURE 2 is a sectional view of the plunger assembly and FIGURE 3 is an exploded view of the plunger assembly.

FIGURE 1 illustrates a bow which has a conventional grip and a bow window formed with a shoulder 11. A sighting plate 13 may be mounted on the bow and has a peep sight 14 which can be adjusted on the sight by thumb screw 16.

An arrow rest 18 extends outwardly from the bow parallel to shoulder 11 and arrow 17 is placed on the rest 18. The back of the bow 12 faces the archer in use.

A plunger assembly 19 is mounted in the bow and has an arrow engaging spring loaded plunger 36 which engages the side of arrow 17 as it lies on the rest 18.

The plunger assembly is shown in the exploded view of FIGURE 3.

A collar member 22 is formed with internal threads and has an externally threaded extension 23 which is formed with an internal opening 24. The extension 23 ice may be threaded into an opening formed in sighting plate 13 for that purpose or where no sighting plate is on the how, an opening may be formed for a mounting collar 43 which is threaded onto extension 23.

An internally and externally threaded sleeve 26 is threaded into collar member 22. The bow 10 is drilled and the assembly is placed in the bow as shown in FIGURE 2. A washer 27 and nut 28 are received on sleeve 26 and lock the assembly to the bow. A plunger holding and adjusting member 33 has a knurled knob 34 and is threaded into sleeve 26. Plunger 36 extends from the end of member 33 and through opening 24 in member 23. A collar 37 on plunger 36 engages the end of member 33 to limit its outward motion. A pin 38 extends from plunger 36 and a spring 39 fits about it. A set screw 41 is threaded into member 33 and has a slot 42 to allow the tension on the spring 39 to be adjusted.

A lock washer 29 and lock nut 31 fits over member 33 to lock it to a preset position.

In operation, the bow is drilled to receive the plunger assembly 19 and the sighting plate 13 is drilled and tapped to receive extension 23. The plunger assembly is inserted into the opening and washer 27 and nut 28 are tightened against the bow. The adjusting member 33 is rotated until the desired length of plunger 36 extends from the sighting plate and the set screw 32 is then tightened against the nut 28 to lock the member 33.

The set screw 41 is adjusted to produce the desired tension on the plunger 36. The plunger may be made of Teflon or other suitable plastic or metal material.

Each archer can adjust the length of plunger 36 to his individual needs by merely unlocking nut 32 and turning knob 34. Also the exact tension on the plunger may be adjusted by moving set screw 41.

It is seen that this invention provides a plunger assembly for a how that may be adjusted in length and tension to an individual archers requirements.

Although it has been described with respect to a preferred embodiment, it is not to be so limited in application. Changes and modifications can be made as defined by the appended claims.

I claim:

1. A plunger assembly for engaging the shaft of an arrow comprising, a housing receivable in or on a how, a plunger assembly mounted in the housing and having a spring-biased plunger which extends out of the bow and engageable with the side of the shaft of an arrow, an arrow rest attached to the bow below said plunger, said plunger moveable into said bow by the shaft of the arrow, and means for adjusting the spring bias of said plunger.

2. In apparatus according to claim 1 a collar within the housing and adjustable relative thereto to adjust the full extended position of the plunger.

3. In apparatus according to claim 1 wherein the means for adjusting the spring bias consists of a set screw threaded into the housing and bears against the spring to adjust the tension in the spring.

References Cited UNITED STATES PATENTS 6/1936 Salomon. 2/1966 Guyton 12441 XR U.S. Cl. X.R. 124-41 

